Matera is a town built into caves using negative architecture and one of the oldest and continuously inhabited human settlements in the world. It was named a UNESCO World Heritage Site because of its underground cistern and water collection system. The main cistern has a water capacity of five million liters and took over 200 years to dig/carve out of the rock!

One of six units in a “Treehotel,” which recently opened 40 miles south of the Arctic Circle in Sweden. The units are constructed from sustainably harvested wood and have electric radiant floor heating and “a state-of-the-art, eco-friendly, incineration toilet.” Full story here.

What do you do when you have a large bookcollection? And we mean a ridiculously large collection. Well, you could live in an entire house lined with bookshelves like this one! Designed by Japan’s Kazuya Morita Architecture Studio in Moriguchi City, the entire interior of the home, which has been dubbed Shelf-Pod, is lined with an extensive latticework of laminated pine board. The designers even created a mosque-like domed roof for the house since the homeowner’s book collection consists primarily of Islamic history texts.